iii. (4 pts) Compute the test statistic. iv. (2 pts) At a = 0.05 level of significance, test whether the true proportion of passengers who prefer aisle seats is significantly greater than 25%. Problem 3: (20 pts) Suppose that the cholesterol level of women at ages 20-29 is normally distributed with a mean of 172 (in mg/dL) and standard deviation of 32.2 (in mg/dL). Suppose 20 women at ages 20-29 are selected at random. Let X be the mean cholesterol level of a sample of 16 women at ages 20-29. (a) (8 pts) Determine the mean and the standard deviation of the sampling distribution of X. (b) (2 pts) Circle the correct answer: Sampling distribution of X is a (Normal / Approximately Normal) distribution.en diferentes ente (c) (10 pts) Find the probability that the sample mean cholesterol level is more than 175 (mg/dL). Problem 4: (25 pts) According a study, 12% of U.S. adults with online services currently read e-books. Assume that this percentage is true for the current population of U.S. adults with online services. A random sample of 750 adults with online services is selected. Let X be the number of adults who read e-books out of those 600 adults. (a) (5 points) Is X a binomial random variable? If "Yes", identify n and p. (b) (8 points) Compute the mean and standard deviation of X. di) SVI lo nsom s die (c) (4 points) Check whether the Normal approximation to Binomial distribution is appropriate in this study. To nobudiggity galkomen (d) (8 points) What is the approximated probability that number of adults who read e-books is at most 100